Micro Switch 1548M 10/100 Switch Installation and Configuration - Configuring and Monitoring from the Switch Manager [Cisco 1548 Series Micro Switch]

Table Of Contents

Configuring and Monitoring from the Switch Manager

Navigating in the Switch Manager

Saving Your Changes

Assigning or Changing Basic Switch Information

Assigning or Changing the Switch Name and Description

Assigning or Changing the Switch Password

Using the Switch Image to Monitor the Switch

LEDs on the Switch Image

Using Telnet to Open a CLI Session

Connecting to Cisco Systems' Resources

Changing the Port Settings

Enabling or Disabling a Port

Checking the Port Status

Changing the Port Duplex Mode

Changing the Port Transmission Speed

Assigning or Changing a Port Name or Description

Checking or Resetting Port Statistics

Maintaining the Address Table

Removing Addresses from the Address Table

Changing the Switch IP Information

Changing the SNMP Settings

Changing the SNMP Read and Write Community Strings

Assigning or Changing Trap Managers

Enabling or Disabling Trap Generation

Assigning or Changing Write Managers

Monitoring Port Activity

Enabling or Disabling Port Monitoring

Changing the CDP Settings

Displaying CDP Neighbors

Enabling or Disabling CDP on the Switch

Changing the CDP Settings

Enabling or Disabling CDP on a Port

Assigning Ports to Different VLANs

Assigning Ports to or Removing Them from a Specific VLAN

Assigning Ports to or Removing Them from Multiple VLANs

Changing the Spanning-Tree Protocol Settings

Checking the Current Spanning-Tree Root Settings

Changing the Spanning-Tree Options for the Switch

Changing the Spanning-Tree Parameters for a VLAN and Its Ports

Checking the Port Status and Forwarding Status

Checking or Resetting Exception and Utilization Statistics

Resetting Port and Switch Statistics

Checking Exception Statistics

Checking Utilization Statistics

Changing the System Configuration

Configuring the Switch Console Port

Changing the CLI Inactivity Timeout Setting

Upgrading the Switch Firmware

Configuring and Monitoring from the Switch Manager

This chapter explains how to use the Cisco 1548 Switch Manager to change the configuration settings and to monitor the switch. This chapter assumes that you have already performed the following tasks described in this guide or in the Cisco 1548M Micro Switch 10/100 Cabling and Start Up.

•"Connecting to the Console Port" section

•"Assigning IP Information to the Switch" section

•"Accessing the Management Interfaces" section

Note   Procedures for changing the configuration settings and detailed descriptions of the fields are also provided in the switch manager online help.

Navigating in the Switch Manager

At the top of each switch manager page is a menu bar. Figure 3-1 describes the functions of the pages accessible from the menu bar.

Note   On Netscape Communicator only, when the cursor is above a topic on the menu bar, a pop-up briefly describes the options on that particular page.

Figure 3-1 Switch Manager Menu Bar

Saving Your Changes

You can change the switch settings by entering information into fields, adding and removing list items, or selecting and deselecting check boxes. Click Apply to save your changes. Click Revert to discard all your unsaved changes and return the previous settings to the page.

Note   After you click Apply, you cannot revert to the previous settings.

•When you enter information in fields and select or deselect check boxes, the changes are saved and immediately take effect after you click Apply.

•When you add items to or remove them from lists, the changes take effect immediately. It is not necessary to click Apply.

Note   Wait approximately 30 seconds before turning off the switch to be sure the changes are saved.

Assigning or Changing Basic Switch Information

You can assign or change basic descriptions about the switch from the switch manager (Figure 3-2). You can also assign a password to the switch management interfaces (switch manager and CLI-privileged commands) and monitor network activity through the live switch image. This page also provides a hotlink that opens a Telnet session to the switch command-line interface (CLI), in addition to hotlinks for contacting Cisco Systems' resources.

Click HOME on the menu bar to display the (Figure 3-2) and check and change switch information.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help from the to access this information online.

Figure 3-2 Home Page

Assigning or Changing the Switch Name and Description

You can assign or change the following information about the switch (be sure to click Apply to save changes):

•Name (maximum of 255 characters)

•Physical location (maximum of 255 characters)

•Name of the person responsible for managing the switch (maximum of 255 characters)

Assigning or Changing the Switch Password

By default, no password is assigned to the switch management interfaces. You can restrict access to the switch manager or CLI-privileged commands by assigning a password. If a user fails to enter the password within a set number of attempts, the switch sends an SNMP trap to the SNMP trap manager to alert you, via in-band management messages, of the failed attempts. (For information about trap managers, see the "Changing the SNMP Settings" section.)

When a password is assigned, the password prompt is displayed when you or any other user opens a switch manager session and displays the . The is redisplayed only after you enter the correct password. If the password prompt reappears, reenter the correct password.

Note   The management station from which you are assigning or changing the password must be connected to the switch console port.

To assign or change the password to the switch manager or CLI-privileged commands:

Step 1 Enter a character string (4 to 8 characters, case sensitive) in the Assign/Change Password field.

Step 2 Enter the same character string in the Reconfirm Password field.

Step 3 Click Apply.

The connection with the switch is broken. The browser prompts you for the new password.

Step 4 Enter the new password at the password authentication prompt, and click OK.

If you have forgotten or do not know the password, see the "Recovering from a Lost or Forgotten Password" section.

Using the Switch Image to Monitor the Switch

The displays the rear panel of the switch (Figure 3-3). The following sections provide information on how to use the switch image.

Figure 3-3 Switch Image

LEDs on the Switch Image

The switch image on the shows the rear-panel LED colors at the last poll interval and refreshes every 30 seconds. The LEDs show port status, speed, and duplex mode (see ).

Table 3-1 Descriptions of the LEDs on the Switch Image

LED Color

Description

Port Status (RJ-45 port images)

Blue (off)

No link.

Solid green

Link is up.

Port Speed

Blue (off)

Operating at 10 Mbps.

Solid green

Operating at 100 Mbps.

Port Duplex

Blue (off)

Operating at half-duplex mode.

Solid green

Operating at full-duplex mode.

Using Telnet to Open a CLI Session

Click Telnet to open a session on the switch command-line interface (CLI).

Connecting to Cisco Systems' Resources

The provides these hotlinks to connect to Cisco Systems' resources:

•Click Cisco Connection Online (CCO) to display the CCO home page (www.cisco.com), which contains links to the support sites for downloading the latest software and displaying the latest Cisco documentation.

•Click Technical Assistance Center (TAC) to open a new message composition window to send e-mail to TAC (tac@cisco.com). You can also phone TAC at 800-553-2447 or 408-526-7209.

•Click HTML Interface Development Group to open a new message composition window to send e-mail to the switch manager development group (cs-html@cisco.com).

Changing the Port Settings

By default, each 10/100 network port on the switch is enabled to transmit packets to and receive them from the device to which it is connected, automatically matching its speed and duplex mode.

Click PORT on the menu bar to display the (Figure 3-4), check the status of the port, and change the port settings.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help from the to access this information online.

Figure 3-4 Port Management Page

Enabling or Disabling a Port

By default, all ports are enabled. To disable a port:

Step 1 In the Status: Requested/Actual column, deselect the Enable check box.

Step 2 Click Apply.

A linkDown trap is sent to the management station if you configured an SNMP manager.

To reenable a port:

Step 1 In the Status: Requested/Actual column, select the Enable check box.

Step 2 Click Apply.

A linkUp trap is sent to the management station if you configured an SNMP manager.

Checking the Port Status

The Status: Requested/Actual column displays the actual status of the port. Each port is always in one of these link states:

Link Up

Port can transmit and receive data.

Link Down

Port is unable to transmit or receive data.

Changing the Port Duplex Mode

Full-duplex operation is simultaneous transmission of data in both directions across a link. For example, a 100BaseTX switched port operating in full-duplex mode can provide up to 200 Mbps of bandwidth across the switched link.

When autonegotiation is selected on the port, it automatically configures for full-duplex operation if the connected device also supports full duplex. If the attached device does not support full-duplex operation, the port automatically configures to half-duplex operation.

To change the port duplex mode:

Step 1 From the Duplex Mode: Requested/Actual drop-down list, select Half, Full, or Auto (autonegotiate). The default is Auto.

Step 2 Click Apply.

Note   If the other device does not autonegotiate, the switch port automatically negotiates to half duplex.

Changing the Port Transmission Speed

By default, the port automatically matches the transmission speed of the attached device. To change the port transmission speed:

Step 1 From the Speed: Requested/Actual drop-down list, select 10 Mbps, 100 Mbps, or Auto (autonegotiate). The default is Auto.

Step 2 Click Apply.

Note   If the other device does not autonegotiate, the switch port automatically negotiates to 10 Mbps.

Assigning or Changing a Port Name or Description

To assign a name or description to a port:

Step 1 In the Port Name/Description column, enter the port name or a description
(up to 80 characters) of how the port is connected.

Step 2 Click Apply.

Checking or Resetting Port Statistics

From the , select a port, and click View to see the statistics for a particular port on the switch. The (Figure 3-5) for the selected port displays the port statistics. lists the statistics displayed on the page:

The switch manager does not automatically refresh the statistics shown on this page. Click Reload to refresh the statistics shown on this page.

Figure 3-5 Detailed Port Statistics Page

Table 3-2 Error Descriptions on the

General Statistics

Good-Packet Bytes Received

Total number of bytes received as part of good packets by the port.

Good Packets Received

Total number of good packets received by the port.

Bytes Sent

Total number of bytes sent by the port.

Packets Sent

Total number of packets sent by the port.

Late Collisions

Number of times the switch detects a collision on the port later than 512 bit-times into the transmission of a packet.

MAC Receive Errors

Number of times the port receives an invalid MAC frame.

RMON Statistics

Total Bytes Received

Total number of bytes received by the port.

Total Packets Received

Total number of packets received by the port.

Broadcast Packets Received

Total number of broadcast packets received by the port.

Multicast Packets Received

Total number of multicast packets received by the port.

CRC/Alignment Errors

Number of alignment errors (caused if all bytes are not received whole) or frames with CRC errors received by the port.

Oversize Packets

Number of packets longer than 1518 bytes received by the port.

Fragments

Number of SMT packets received by the port.

Very Long Events

Number of packets that exceed the maximum length prescribed in IEEE 802.3.

Collisions

Number of times the port and the connected device attempt to transmit at the same time.

64-Byte Packets
65-127-Byte Packets
128-255-Byte Packets
256-511-Byte Packets
512-1023-Byte Packets
1024-1518-Byte Packets

Number of packets received in these lengths in bytes.

Maintaining the Address Table

The switch learns the MAC addresses of connected devices, adding these addresses to the address table. The switch supports multiple addresses on each port and stores up to 4096 addresses.

Click ADDRESS on the menu bar to display the (Figure 3-7), check the address table, and remove addresses from the table.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help from the to access this information online.

Figure 3-6 Address Table Management Page

Removing Addresses from the Address Table

When the address table exceeds the maximum MAC address limit (4096), switch performance can be degraded.

To remove specific addresses from the table one at a time:

Step 1 Select the addresses on the Address Table list.

Step 2 Click Remove.

To remove all addresses from the table, click Remove All.

Changing the Switch IP Information

IP information identifies the switch to the network and is necessary to manage the switch through the switch manager, the CLI, or SNMP. This information is usually assigned to the switch after it is installed and initially started up. (See the "Assigning IP Information to the Switch" section.)

The IP Address field displays the current IP address of the switch. Click IP on the menu bar to display the (Figure 3-7) and change switch IP information.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-7 IP Management Page

Caution   Changing the switch IP address on this page will end your switch manager session. To open a new session, enter the new IP address in the URL field if you are using Communicator (the Address field if you are using Internet Explorer).

To change the switch IP information:

Step 1 Select User-Configured from the IP State drop-down list.

Note   You can manually change the switch IP information only if the User-Configured option is enabled.

Note   Use the BootP Get IP option if you want the BootP (Boot Protocol) server to assign the IP information. The switch must be connected to a network that has a BootP server. The BootP Get IP option becomes active when you restart the switch. If this option is enabled, you cannot manually change IP information.

The default is User-Configured.

Step 2 Enter a new IP address for the switch in the IP Address field.

Caution   If you enter a new address and click Apply, the switch manager loses contact with the switch. Enter the new IP address of the switch in the Location field if you are using Communicator (the Address field if you are using Internet Explorer) to redisplay the switch manager.

Step 3 Enter the subnet mask for the switch.

The subnet mask must be in the same subnet as the IP address.

Step 4 Enter the IP address of the default gateway.

The default gateway is the router that the switch uses to reach IP subnets other than the local subnet to which the switch is attached.

Step 5 Click Apply.

Changing the SNMP Settings

SNMP provides the means to manage and monitor the switch through the Management Information Base (MIB) objects. Additional information about SNMP and MIB objects is provided in the "Overview of SNMP" section and the "Accessing the MIB Files through SNMP" section.

Click SNMP on the menu bar to display the (Figure 3-8) and check and change the SNMP settings.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-8 SNMP Management Page

Changing the SNMP Read and Write Community Strings

Community strings serve as passwords for SNMP messages. You can assign community strings that enable the switch to validate SNMP read and read-write requests from a management station.

To change the SNMP Read community string:

Step 1 Enter up to 32 characters in the Read Community String field. The default is public.

Step 2 Click Apply.

To change the SNMP Write community string:

Step 1 Enter up to 32 characters in the Write Community String field. The default is private.

Step 2 Click Apply.

Assigning or Changing Trap Managers

A trap manager is an SNMP management station that receives traps, which are the system alerts generated by the switch. If no trap manager is defined, no traps are issued. Up to four trap managers and their accompanying community strings can be entered.

To assign a trap manager:

Step 1 Enter the IP address and a community string (up to 32 characters) in the IP Address and Trap Manager Community String fields.

Step 2 Click Add.

To remove a trap manager:

Step 1 Select the manager from the Current list.

Step 2 Click Remove.

Enabling or Disabling Trap Generation

By default, the Enable Authentication Trap Generation check box is selected (meaning this parameter is enabled). When this check box is selected, the switch generates authentication traps that alert a management station to SNMP requests that are not accompanied by a valid community string. However, even if this parameter is enabled, no trap can be generated if no trap manager addresses are specified. (For information about trap manager settings, see the "Assigning or Changing Trap Managers" section). If you change this check box, click Apply to save your changes.

By default, the Enable Link Up/Link Down Trap Generation check box is selected (meaning this parameter is enabled). If you change this check box, click Apply to save your changes.

The switch generates linkDown traps when a port is suspended or disabled for these reasons:

•User disables the port.

•Link is down.

The switch generates linkUp traps when a port is enabled for these reasons:

•Presence of linkbeat.

•Management intervention enables the port.

Assigning or Changing Write Managers

A write manager is an SNMP management station that can issue write requests to the switch. Up to four IP addresses of stations can be defined.

To assign a write manager:

Step 1 Enter the management station IP address in the IP Address field.

Step 2 Click Add.

To remove a write manager:

Step 1 Select the manager from the Current list.

Step 2 Click Remove.

Monitoring Port Activity

By enabling the Switched Port ANalyzer (SPAN), you can forward the incoming and outgoing traffic of one switch port in the same VLAN and monitor that traffic from another switch port. You can also use a network analyzer on the monitoring port to troubleshoot network problems by examining the traffic on other Cisco switched ports or segments.

By default, no port on the switch is designated as the monitoring port, and no ports on the switch are monitored. Remember the following restrictions when monitoring ports:

•The monitoring port cannot be a member of more than one VLAN.

•The monitoring port can monitor only one port at a time.

•Do not make VLAN membership changes on the monitoring port or monitored ports until after you disable monitoring.

Click SPAN on the menu bar to display the () and change the monitoring settings.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-9 SPAN Configuration Page

Enabling or Disabling Port Monitoring

To enable one port to monitor traffic on another port:

Step 1 Select the Capturing Frames to the Monitoring Port check box. By default, this check box is not selected (meaning port monitoring is disabled).

Step 2 From the Select Monitoring Port drop-down list, select the monitoring port (the port to which captured frames are sent).

You can designate any port as the monitoring port, but the following restrictions apply:

•The monitoring port cannot be a member of more than one VLAN.

•The monitoring port can monitor only one port at a time.

•Do not make VLAN membership changes on the monitoring port or monitored ports until after you disable monitoring.

Step 3 From the Select Monitored Port drop-down list, select the port that you want to monitor.

Step 4 Click Apply.

Note   When you enable port monitoring, the system provides alerts that inform you that all ports on the switch will behave as if they belong to VLAN 1. Actually, no VLAN assignments are lost; all VLAN assignments are saved in Flash memory. When you disable port monitoring, all ports will operate according to their VLAN assignments.

No alerts are provided if you enable port monitoring via SNMP.

To disable port monitoring:

Step 1 Deselect the Capturing Frames to Monitoring Port check box.

Step 2 Click Apply.

Changing the CDP Settings

The Cisco Discovery Protocol (CDP) enables the switch to advertise its existence to other Cisco devices in the network. When CDP is enabled, the switch manager and network management applications have an accurate picture of the network at any time because CDP gathers information about device types, links between devices, and the number of interfaces within each device.

By default, CDP is not enabled on the switch and all its ports.

Click CDP on the menu bar to display the (Figure 3-10) and check and change the CDP settings.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-10 CDP Management Page

Displaying CDP Neighbors

The Discovered Neighboring Devices list shows the devices with which the switch exchanges CDP messages. To display information about neighboring devices:

Step 1 From the Discovered Neighboring Devices list, select a device.

Step 2 Click one of these buttons:

•Click Browse to access the web console of a neighboring device. The neighbor must be a device that has web-console support.

•Click Telnet to open a Telnet session and log into a neighboring device.

•Click Details to display the detailed CDP information currently stored in the switch.

Enabling or Disabling CDP on the Switch

By default, CDP is disabled on the switch. If you want the switch to exchange information with Cisco devices, you can enable CDP on the switch. To enable CDP:

Step 1 Select the Enable CDP check box.

Step 2 Click Apply.

To disable CDP:

Step 1 Deselect the Enable CDP check box.

Step 2 Click Apply.

Changing the CDP Settings

To change the global CDP settings for the switch:

Step 1 In the Packet Hold Time field, enter the number of seconds (between 10 and 255) that a neighboring device retains the CDP neighbor information received from this switch. The default setting is 180 seconds.

If a neighboring device does not receive a CDP message before the hold time expires, the device drops this switch as a neighbor. The packet hold time should be higher than the packet transmission time.

Step 2 In the Packet Transmission Time field, enter the number of seconds
(between 5 and 900) between transmissions of CDP messages. The default is 60 seconds. The packet transmission time should be lower than the packet hold time.

Step 3 Click Apply.

Enabling or Disabling CDP on a Port

By default, CDP is disabled on all ports on the switch. If you want a port to exchange information with Cisco devices, you can enable CDP on that port. To enable CDP on a port:

Step 1 Select the port from the CDP Enabled list.

Step 2 Click Enable.

To disable CDP on a port:

Step 1 Select the port from the CDP Disabled list.

Step 2 Click Disable.

Assigning Ports to Different VLANs

A virtual LAN (VLAN) is a defined broadcast domain logically segmented by function, team, or application. Through VLANs, you can enhance network performance by allowing the transmission of traffic among member stations in the same VLAN and by blocking traffic from stations in other VLANs.

By default, all ports on the switch are assigned to VLAN 1, which is the management VLAN. You can create up to four VLANs on the switch and assign each switch port to one or all VLANs.

Note   Only VLAN 1 supports Spanning-Tree Protocol (STP).

Click VLAN on the menu bar to display the (Figure 3-11) and assign ports to VLANs other than VLAN 1.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-11 VLAN Management Page

Assigning Ports to or Removing Them from a Specific VLAN

A simple port-based VLAN consists of a switch port assigned to one VLAN. By default, all ports are assigned to VLAN 1. To assign a port to a different VLAN:

Step 1 In the VLAN drop-down list, select 2, 3, or 4.

Step 2 Click Apply.

To remove a port from a VLAN membership other than VLAN 1:

Step 1 In the VLAN drop-down list, select 1.

Step 2 Click Apply.

Assigning Ports to or Removing Them from Multiple VLANs

An overlapping VLAN is a port (a multi-VLAN port) assigned to more than one VLAN and is usually connected to a server or router. This allows the stations on all VLANs to reach the server or router.

Note   A multi-VLAN port cannot be designated as a monitoring port. For more information about port monitoring, see the "Monitoring Port Activity" section.

The multi-VLAN port functions normally in all its VLANs. For example, when an unknown MAC address is received on the multi-VLAN port, it is learned by all the port VLANs. The port also responds to the STP messages generated by separate instances of Spanning-Tree Protocol (STP) in each VLAN. Because the multi-VLAN port is a member of all VLANs, flooded traffic received on the port is forwarded to ports in all VLANs.

Caution   To avoid unpredictable activity by STP, do not connect a port assigned to all VLANs to another switch or hub. Connect these ports only to routers or servers.

To assign a port to all VLANs:

Step 1 In the VLAN drop-down list, select All.

Step 2 Click Apply.

Changing the Spanning-Tree Protocol Settings

The Spanning-Tree Protocol (STP) constructs network topologies that do not contain loops. When the network configuration changes, STP transparently reconfigures bridges and switches to avoid the creation of loops. STP avoids loops by placing ports in a forwarding or blocking state and establishes redundant paths (in the event of lost connections). The VLAN is treated as a separate bridge, and a separate instance of STP is applied to it.

STP requires approximately 30 seconds to complete its discovery of the network, and the switch does not forward packets during this time.

By default, STP is enabled only on VLAN 1 and cannot be enabled on other VLANs.

Click STP on the menu bar to display the (Figure 3-12) and change the appropriate STP settings for the switch and for the ports assigned to specific VLANs.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-12 Spanning-Tree Management Page

Note   You can enable STP on VLAN 1 only. The Go button and the VLAN 2, 3, 4, and All options from the Select VLAN drop-down list are automatically disabled when you select the Enable Spanning Tree check box.

None of the fields (such as operating parameters and STP switch settings) apply to VLAN 2, 3, 4, or All. In addition, the STP port settings do not apply to any ports assigned to VLAN 2, 3, 4, or All.

Note   The ports listed in Figure 3-12 shows that ports 1, 2, and 3 belong to VLAN 1. The only shows the ports assigned to VLAN 1.

Checking the Current Spanning-Tree Root Settings

The Operating Parameters section displays the following read-only STP settings for the current root switch, which could be defined on another switch.

Bridge ID

Unique hexadecimal ID number that has a bridge priority and a unique MAC address.

Number of
Member Ports

Number of ports configured with STP.

Max Age

Number of seconds a bridge waits for STP configuration messages before attempting a reconfiguration.

Hello Time

Number of seconds between the transmission of STP configuration messages. All bridges send configuration messages during reconfiguration to elect the designated root bridge. After STP completes its network discovery, only designated bridges send configuration messages.

Topology Changes

Number of bridge topology changes experienced by the network. A topology change occurs as ports on any bridge change from a nonforwarding to a forwarding state or when a new root is selected.

Designated Root

ID number of the bridge identified as the root by the STP.

Root Port

Port on this bridge with the lowest-cost path to the root bridge. This option identifies the port through which the path to the root bridge is established. N/A is displayed when STP is disabled or when this bridge is the root bridge.

Root Path Cost

Cost of the path from this bridge to the root bridge shown in the Designated Root field. It equals the path cost parameters held for the root port.

Forward Delay

Number of seconds before a port changes from its STP learning and listening states to a forwarding state. Every bridge on the network ensures that no loop is formed before the port can forward packets.

Last TopChange

Number of days (d), hours (h), minutes (min), and seconds (s) since the last topology change.

Changing the Spanning-Tree Options for the Switch

The Spanning Tree Configuration section displays a list of STP parameters that this switch will use when it is the root switch. To change the STP configuration on this switch:

Step 1 Enable STP if you have previously disabled it:

(a) Select the Enable Spanning Tree check box to enable STP.

(b) Click Apply.

Note   You can enable STP on VLAN 1 only. The Go button and the VLAN 2, 3, 4, and All options from the Select VLAN drop-down list are automatically disabled when you select the Enable Spanning Tree check box.

Note   You can slightly improve performance on the switch by disabling STP. However, disable STP only if you are sure there are no loops in your network topology. With STP disabled and loops present in the topology, network performance is degraded by excessive traffic and indefinite packet duplication.

Step 2 In the Bridge Priority field, enter the value (0 to 65535) used in determining the root bridge. The bridge with the lowest value has the highest priority and is selected as the root. The default is 32768.

Step 3 In the Hello Time field, enter the number of seconds (1 to 10) after which this switch becomes the root bridge. The default is 2.

Step 4 In the Max Age field, enter the number of seconds (6 to 40) a switch waits for STP configuration messages before it attempts a reconfiguration. The default
is 20.

Step 5 In the Forward Delay field, enter the number of seconds (4 to 30) a port waits before changing from its STP learning and listening states to the forwarding state. This delay time is necessary to ensure that no loop is formed before the switch forwards a packet. The default is 15.

Note   Each switch in a spanning tree adopts the Hello, Max age, and Delay parameters of the root bridge regardless of how it is configured.

Step 6 Click Apply.

Changing the Spanning-Tree Parameters for a VLAN and Its Ports

You can set STP parameters for VLAN 1 only on the switch. The Current VLAN field displays VLAN 1 when the STP settings are displayed. The Port Parameters list displays only ports that are members of VLAN 1, and the settings determine how the port responds if a loop is formed.

To modify spanning-tree parameters for VLAN 1 and its ports:

Step 1 In the Select VLAN drop-down list, select 1.

Note   You can enable STP only on VLAN 1. The Go button and the VLAN 2, 3, 4, and All options from the Select VLAN drop-down list are automatically disabled when you select the Enable Spanning Tree check box.

Step 2 Click Go.

The displays the current spanning-tree parameter settings and the member ports of VLAN 1.

Step 3 Enable STP if you have previously disabled it. By default, STP is enabled on VLAN 1.

(a) Select the Enable Spanning Tree check box to enable STP.

(b) Click Apply.

Note   You can slightly improve performance on the switch by disabling STP. However, disable STP only if you are sure there are no loops in your network topology. With STP disabled and loops present in the topology, network performance is degraded by excessive traffic and the indefinite packet duplication.

Step 4 In the Path Cost column, enter a number from 1 to 65535 for each port. The default is 19.

The path cost is inversely proportional to the LAN speed of the network interface at the port. A high path cost means the port has low bandwidth and should not be used, if possible. A lower path cost represents higher-speed transmission; this setting can affect which port remains enabled in the event of a loop.

Note   We recommend setting the path cost to 100 if the port is set to run at 10 Mbps.

Step 5 In the Priority column, enter a number from 1 to 255 for each port. The default is 128. The lower the number, the higher the priority.

Step 6 In the Port Fast Mode column, select a port, and select the check box to enable the Port Fast feature (if the port is connected to an end station). The default is Disabled (check box is not selected).

The Port Fast feature immediately brings a port from the blocking state into the forwarding state by eliminating the forward delay (the amount of time a port waits before changing from its STP learning and listening states to the forwarding state). Port Fast Mode-enabled ports should only be used for end-station attachments.

Step 7 Click Apply.

Checking the Port Status and Forwarding Status

The State column displays the state of the port. A port can be in one of the following states:

Blocking

The port is not forwarding frames and is not learning new addresses.

Listening

The port is not forwarding frames but is progressing toward a forwarding state. The port is not learning addresses.

Learning

The port is not forwarding frames but is learning addresses.

Forwarding

The port is forwarding frames and learning addresses.

Disabled

The port has been removed from STP operation. Administrative intervention is required to enable the port.

The Forward Transitions column displays the number of times STP changed forwarding states.

Checking or Resetting Exception and Utilization Statistics

To see the exception and utilization statistics for the switch, Click STATISTICS on the menu bar to display the (Figure 3-13) and check the switch statistics.

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-13 Statistics Reports Page

Resetting Port and Switch Statistics

To reset the statistics of a switch port:

Step 1 Select the port from the Select Port list.

Step 2 Click Reset Port Statistics.

To reset the statistics for all ports on the switch, click Reset All Statistics.

The switch manager does not automatically refresh the statistics shown on this page. Click Reload to refresh the statistics shown on this page.

Checking Exception Statistics

This report displays the number of receive and transmit errors for each port.

Receive

Number of giants and FCS and alignment errors.

Transmit

Number of excessive deferrals, late collisions, jabber errors, and other transmit errors.

Checking Utilization Statistics

This report displays the number of bytes received and transmitted for each port.

Receive

Number of bytes received in good packets.

Transmit

Number of bytes transmitted.

Changing the System Configuration

Cisco periodically provides new firmware to implement enhancements and maintenance releases. New firmware releases can be downloaded from Cisco Connection Online (CCO), the Cisco Systems' customer web site available at the following URLs: www.cisco.com, www-china.cisco.com, and www-europe.cisco.com.

The Firmware Version field displays the firmware version in use. You can download the latest switch firmware from a TFTP server.

Note   When you download the firmware permanently to Flash memory, the switch does not respond to commands for approximately 1 minute. This is normal and correct. Do not turn off the switch. The switch then resets and begins using the new firmware.

Caution   If you interrupt the transfer by turning the switch off and on, the firmware could get corrupted. For recovery procedures, see the "Recovering from Corrupted Firmware" section.

If you want to upgrade the switch firmware, click SYSTEM on the menu bar to display the (Figure 3-14).

Note   This section provides detailed information about this page and procedures on changing the settings. When you are using the switch manager, click Help on the to access this information online.

Figure 3-14 System Configuration Page

Configuring the Switch Console Port

The console port on the switch provides terminal and PC access to the switch. After the switch is installed, be sure to configure the console port settings of the switch to match the settings of the terminal or PC.

These are the default settings of the switch console port:

•Baud rate default is 9600.

•Data bits default is 8.

Note   If data bits is 8, set parity to None.

•Stop bits default is 1.

•Parity settings default is None.

If you change any of these settings, click Apply to save your changes.

Changing the CLI Inactivity Timeout Setting

You can change the number of seconds that the CLI can wait without activity before it times out. After timeout, you must reenter the password.

To change the inactivity timeout parameter:

Step 1 Enter the number of seconds (0, or 30 to 65500) in the CLI Inactivity Timeout field. The default is 0 (which means the console session does not time out).

Step 2 Click Apply.

Upgrading the Switch Firmware

The Firmware Version field displays the firmware version used by the switch. You can upgrade the firmware by following these steps to download the latest firmware from a TFTP server to your switch:

Step 1 In the Server IP Address field, enter the IP address of the TFTP server on which the upgrade file is located.

Step 2 Enter the upgrade filename (up to 80 characters) in the Filename for Firmware Upgrades field.

Step 3 Select one of these download modes:

•Permanent to download the firmware to Flash memory.

•Temporary to download the firmware to DRAM. Use this option to test the new firmware before overriding the previous firmware. After a power cycle, the switch discards the new firmware and uses the previous firmware.

The default is Permanent.

Step 4 Click System TFTP Upgrade to download the upgrade file from the TFTP server to the switch.

Step 5 Click OK on the confirmation prompt.

Note   When you download the firmware permanently to Flash memory, the switch does not respond to commands for approximately 1 minute. This is normal and correct. Do not turn off the switch. The switch then resets and begins using the new firmware.

Caution   If you interrupt the transfer by turning the switch off and on, the firmware could get corrupted. For recovery procedures, see the "Recovering from Corrupted Firmware" section.